Research and Application Status of Flux in Preparation of Vanadium-Titanium Magnetite Pellets AITranslate

［1］（刘伟，方一兵，柯家骏. 中国科学院对攀枝花钒钛磁铁矿综合利用之化工冶金研究回顾［J］.工程研究-跨学科视野中的工程，2021，13（4）：381.）

W Liu，Y B Fang，J J Ke. Overview of comprehensive utilization research on chemical metallurgy from Panzhihua mineral resources by Chinese academy of sciences［J］.Journal of Engineering Studies，2021，13（4）：381.

［2］（王绍灼，孟晗，王芬，李燕，唐超. 难变形钛合金的锻造缺陷及预防［J］.锻压技术，2024，49（2）：45.）

S Z Wang，H Meng，F Wang，Y Li，C Tang. Forging defects and prevention on difficult-to-deform titanium alloy［J］.Forging & Stamping Technology，2024，49（2）：45.

［3］（魏科，陈飞，黄龙，胡康宏. 航空大型复杂钛框预锻成形初始毛坯优化［J］.塑性工程学报，2024，31（1）：99.）

K Wei，F Chen，L Huang，K H Hu. Optimization of initial billet for preforging forming of aviation large-sized complex titanium alloy bulkhead［J］.Journal of Plasticity Engineering，2024，31（1）：99.

［4］（王帅，郭宇峰，姜涛，陈凤，郑富强. 钒钛磁铁矿综合利用现状及工业化发展方向［J］.中国冶金，2016，26（10）：40.）

S Wang，Y F Guo，T Jiang，F Chen，F Q Zheng. Comprehensive utilization and industrial development direction of vanadium-titanium magnetite［J］.China Metallurgy，2016，26（10）：40.

［5］（郭宇峰，屈涵宇，陈凤，王帅，杨凌志，张金来. 钛精矿高效分选除杂研究现状［J］.稀有金属，2024，48（12）：1797.）

Y F Guo，H Y Qu，F Chen，S Wang，L Z Yang，J L Zhang. Research status of high-efficiency sorting and impurity removal of titanium concentrate［J］.Chinese Journal of Rare Metals，2024，48（12）：1797.

［6］（梁雪崟，叶国华，朱思琴，亢选雄. 钒钛磁铁矿提钒工艺的研究进展［J］.稀有金属，2023，47（6）：893.）

X Y Liang，G H Ye，S Q Zhu，X X Kang. Research progress of process of vanadium extraction from vanadium-titanium magnetite［J］.Chinese Journal of Rare Metals, 2023，47（6）：893.

［7］（高亮，尹福兴，裴增文，高起方. 复杂氰化尾渣生产球团矿的工艺试验研究［J］.黄金，2023，44（12）：90.）

L Gao，F X Yin，Z W Pei，Q F Gao. Experimental study on the process of pelletizing cyanide tailings with complex mineral composition［J］.Gold，2023，44（12）：90.

［8］（胡鹏，蒋胜，谭阳杰，周密，向绍红. 提高全钒钛球团矿抗压强度技术研究与应用［J］.钢铁钒钛，2022，43（4）：107.）

P Hu，S Jiang，Y J Tan，M Zhou，S H Xiang. Research and application of improving the compressive strength of full V-Ti pellets［J］.Iron Steel Vanadium Titanium，2022，43（4）：107.

［9］（吴胜利，王筱留. 钢铁冶金学 ［M］. 北京：冶金工业出版社，2019. 538.）

S L Wu，X L Wang. Iron and Steel Metallurgy ［M］. Beijing：Metallurgical Industry Press，2019. 538.

［10］（甘敏，范晓慧，陈许玲，袁礼顺，姜涛，赵忠花. 钙和镁添加剂在氧化球团中的应用［J］.中南大学学报（自然科学版），2010，41（5）：1645.）

M Gan，X H Fan，X L Chen，L S Yuan，T Jiang，Z H Zhao. Application of Ca，Mg-additives in oxidized pellets［J］.Journal of Central South University （Science and Technology），2010，41（5）：1645.

［11］（杨柳，隋裕雷. 钒钛磁铁矿球团气基还原粉化和膨胀实验研究［J］.广东化工，2020，47（6）：17.）

L Yang，Y L Sui. Experimental study on gas-based reduction pulverization and swelling of vanadium titano-magnetite pellets［J］.Guangdong Chemical Industry，2020，47（6）：17.

［12］Guo Y F，Liu K，Chen F，Wang S，Yang L Z，Li D Y，Zheng Y. Effect of high-pressure grinding rolls pretreatment on the preparation of vanadium-titanium magnetite pellets［J］.Journal of Materials Research and Technology，2023，23：2479.

［13］（马黎明，张建良，吴胜利，刘征建，王耀祖，徐晨阳.基于熔剂性生球的复合造块工艺处理钒钛磁铁矿［J］.钢铁研究学报，2020，32（6）：462.）

L M Ma，J L Zhang，S L Wu，Z J Liu，Y Z Wang，C Y Xu. Treatment of vanadium-titanium magnetite based on fluxed green ball composite agglomeration process［J］.Journal of Iron and Steel Research，2020，32（6）：462.

［14］Tang J，Chu M，Xue X. Optimized use of MgO flux in the agglomeration of high-chromium vanadium-titanium magnetite［J］.International Journal of Minerals，Metallurgy，and Materials，2015，22（4）：371.

［15］Gao Z，Cheng G，Xue X X，Yang H，Duan P N. Property investigations of low-grade vanadium-titanium magnetite pellets with different MgO contents［J］.Steel Research International，2018，89（6）：1700543.

［16］Liu H，Peng S，Zhang K，Qin Y L，Meng F，He W C，Liu W Q，Chen M，Yan L X. Effect of finely ground limestone and dolomite on compression strength and reduction swelling of vanadium-titanium pellets［J］.Materials，2021，14（16）：4433.

［17］He Z W，Yue H R，Xue X X. Study of the high temperature metallurgical properties of on-site samples with vanadium-titanium magnetite［J］.Transactions of the Indian Institute of Metals，2018，71（8）：2001.

［18］（陈许玲，黄云松，范晓慧，甘敏. 钒钛磁铁矿球团氧化焙烧行为和固结特性［J］.中南大学学报（自然科学版），2016，47（2）：359.）

X L Chen，Y S Huang，X H Fan，M Gan. Oxidation roasting behavior and concretion properties of vanadium-titanium magnetite pellet［J］.Journal of Central South University （Science and Technology），2016，47（2）：359.

［19］Cheng G J，Gao Z X，Yang H，Xue X X. Effect of calcium oxide on the crushing strength，reduction，and smelting performance of high-chromium vanadium-titanium magnetite pellets［J］.Metals，2017，7（5）：181.

［20］Chen B J，Wen J，Jiang T，Li L，Yang G D，Zhao T.Phase evolution behavior and oxidation induration mechanism of high-chromium vanadium-titanium magnetite flux pellets［J］.Metallurgical and Materials Transactions. B，Process Metallurgy and Materials Processing Science，2022，53（1）：178.

［21］Li W，Fu G Q，Chu M S，Zhu M Y. Influence of MgO on the oxidation and induration of Hongge vanadium titanomagnetite pellets［J］.Ironmaking & Steelmaking，2020，47（8）：837.

［22］（田铁磊，师学峰，蔡爽，张彦辉，邢宏伟，李杰. 镁质熔剂性球团孔结构特性［J］.钢铁，2016，51（10）：10.）

T L Tian，X F Shi，S Cai，Y H Zhang，H W Xing，J Li. Pore structure characteristics of magnesian flux pellets［J］.Iron & Steel，2016，51（10）：10.

［23］（郭宇峰，刘阔，刘雅婧，陈凤，王帅，郑富强.铁矿球团还原膨胀机理及影响因素的研究进展［J］.钢铁，2021，56（4）：9.）

Y F Guo，K Liu，Y J Liu，F Chen，S Wang，F Q Zheng. Research progress on reduction swelling mechanism and influencing factors of iron ore pellets［J］.Iron & Steel，2021，56（4）：9.

［24］Guo Y，Liu K，Chen F，Wang S，Zheng F Q，Yang L Z，Liu Y J. Effect of basicity on the reduction swelling behavior and mechanism of limestone fluxed iron ore pellets［J］.Powder Technology，2021，393：291.

［25］（程功金. CaO对高铬型钒钛磁铁矿球团的冶金特性影响研究［A］. 2017年全国高炉炼铁学术年会论文集 ［C］. 昆明：中国金属学会，2017. 422.）

G J Cheng. Study on the influence of CaO on metallurgical properties of high chromium vanadium titanium magnetite pellets［A］. Proceedings of the 2017 National Blast Furnace Ironmaking Academic Annual Conference ［C］. Kunming：The Chinese Society for Metals，2017. 422.

［26］（陈超，孙体昌，寇珏，赵永强. 镁化合物对钒钛磁铁矿精矿碳热还原的影响研究［J］.稀有金属，2018，42（7）：765.）

C Chen，T C Sun，J Kou，Y Q Zhao. Carbothermic reduction of vanadium titanomagnetite concentrate with magnesium compounds［J］.Chinese Journal of Rare Metals，2018，42（7）：765.

［27］Hu Q Q，Xin R，Gao X D，Wang Y，You Y，You Z X，Lv X W. Reduction disintegration behavior of vanadium titanomagnetite pellets in H2-CO-CO2-N2 mixtures［J］.Powder Technology，2023，413：118073.

［28］（刘含笑，刘凯，王祥德，薛婷婷，郭飞，吕东芹，王巍. 电位滴定法测定铁中间合金中铁含量［J］.分析试验室，2024，43（6）：858.）

H X Liu，K Liu，X D Wang，T T Xue，F Guo，D Q Lv，W Wang. Determination of iron content in intermediate ferroalloy by automatic potentiometric titration method［J］.Chinese Journal of Analysis Laboratory，2024，43（6）：858.

［29］Prusti P，Barik K，Dash N，Biswal S K，Meikap B C. Effect of limestone and dolomite flux on the quality of pellets using high LOI iron ore［J］.Powder Technology，2021，379：154.

［30］（袁壮，潘建，朱德庆，郭正启，杨聪聪，王硕，王定政. 钒钛磁铁矿制备镁质熔剂性球团性能研究［J］.烧结球团，2021，46（3）：47.）

Z Yuan，J Pan，D Q Zhu，Z Q Guo，C C Yang，S Wang，D Z Wang. Study on the properties of magnesia flux pellets prepared from vanadium-titanium magnetite［J］.Sintering and Pelletizing，2021，46（3）：47.

［31］（刘文旺，李明，青格勒，黄文斌，田伟杰，骆振勇. 首钢京唐高镁球团工业试验［J］.烧结球团，2012，37（5）：36.）

W W Liu，M Li，G L Qing，W B Huang，W J Tian，Z Y Luo. Industrial test of high magnesia pellet in Shougang Jingtang［J］.Sintering and Pelletizing，2012，37（5）：36.

［32］（雷霄霆. 太钢高炉配用碱性球团生产实践［J］.山西冶金，2019，42（4）：96.）

X T Lei. Practice of alkaline pelletizing production in blast［J］.Shanxi Metallurgy，2019，42（4）：96.

［33］（梁利生，周琦，易陆杰. 宝钢湛江钢铁熔剂性球团稳定生产实践［A］. 第十一届中国钢铁年会论文集 ［C］. 北京：中国金属学会，2017. 6.）

L S Liang，Q Zhou，L J Yi. Production performance of grate-kiln fluxed pellet in Baosteel Zhanjiang iron & steel plant［A］. Proceedings of the 11th China Iron and Steel Annual Conference ［C］. Beijing：The Chinese Society for Metals，2017. 6.

［34］（隋孝利，王英杰，牛宏伟，袁平刚. 承钢圆形竖炉焙烧镁质球团的研究［J］.烧结球团，2015，40（1）：28.）

X L Sui，Y J Wang，H W Niu，P G Yuan. Study on indurating magnesia pellet with cylindrical shaft furnace in Chengde iron and steel company［J］.Sintering and Pelletizing，2015，40（1）：28.

Basic Information:

DOI：10.13373/j.cnki.cjrm.XY23090005

Chinese Library Classification Number:TF044

Citation Information:

Vanadium-titanium magnetite （VTM） is a crucial strategic mineral resource，and it is mainly processed through two methods：blast furnace process and non-blast furnace process. Preparation of high-quality furnace burden is one of the significant steps to improve the utilization efficiency of VTM in both processes. Compared to sinter ore，VTM pellets have great advantages，such as higher iron content and lower energy consumption. In particular，the addition of flux to VTM pellets has been shown to optimize the burden structure and reduce energy consumption during the VTM smelting process，which is helpful for achieving carbon peak before 2030 and carbon neutral before 2060. There are many kinds of microscopic phase in VTM pellets，and the action mechanism of flux containing calcium and magnesium is complicated. The expansion and disintegration of VTM pellets are serious in the reduction process，and flux addition also affects the reduction expansion and disintegration properties. This paper systematically reviewed the current domestic and international research progresses on fluxed VTM pellets. The impacts of three types of fluxes （flux containing calcium，flux containing magnesium，and compound calcium magnesium flux） on the properties of VTM pellets were further studied and compared from perspectives of the properties of green pellets，consolidation behavior，reduction swelling，and reduction disintegration. The preparation of high-quality fluxed VTM pellets was a significant challenge in the VTM smelting process. As for green VTM pellets，when adjusting the basicity of VTM pellets by quicklime within the range of 0.6 to 1.2，both the compressive strength and falling strength exhibited an upward trend with the basicity increased. Under the condition that basicity 1.0，the MgO content in VTM pellets，varied from 1.0% to 3.0%，had little impacts on the falling strength but higher impacts on the compressive strength of green pellets.With the increase of MgO content，the compressive strength initially decreased and then slightly rebounded. The introduction of dolomite into the mixture oredeteriorated the compressive strength of VTM pellets. Interestingly，as the basicity rose from 0.6 to 1.2 due to the addition of dolomite，the falling strength of the pellets gradually increased. The physical properties of the flux itself had great influence on the performance of the green pellets. During the VTM pellets consolidation，the addition of a certain amount of calcium-based flux improved the formation of low-melting point binder phase，which enhanced the consolidation strength and reduced the reduction expansion rate. However，excessive calcium content in VTM pellets were not conducive to improving the consolidation strength and reduction performance considering the perovskite solid solution preferably generated by the combination of calcium and titanium. Thus，the suitable low-melting point binder phase content and less perovskite phase were more beneficial to the consolidation and reduction performance of VTM pellets. Besides，the addition of magnesium-containing fluxes during pellets consolidation led to the formation of stable magnesium-iron solid solution （（Fe_xMg_1-x）O·Fe₂O₃）. This solid solution hampered the recrystallization of titanium-containing hematite and reduced the consolidation strength of VTM pellets. Therefore，the higher the content of gangue phase and magnesium-iron solid solution was，the more difficult to crystallize and recrystallize titanium-bearing hematite in VTM pellets，resulting in poorer consolidation strength of pellets. However，the formation of magnesium-iron solid solution aided in improving the reduction expansion performance of the pellets. The formation of magnesium-iron solid solution phase prevented the reduction of Fe³⁺ to Fe²⁺，which reduced the reduction expansion rate of VTM pellets. What's more，under the combined influence of composite fluxes containing calcium and magnesium，consolidation strength of VTM pellets was superior to that of single magnesium-based fluxed VTM pellets. The efficient utilization of multiple fluxes in VTM pellets could make up for the poor performance of pellets caused by single fluxes. An industrial experiment，aimed at producing magnesium VTM pellets at ironmaking plant, Chengde iron & steel company, Hebei iron & steel （HBIS） group，was successfully conducted to verify the above process route based on magnesium VTM pellets. This experiment used magnesium as an additive. Following meticulous adjustments to the furnace charge structure conditions of the shaft furnace，pellets with commendable metallurgical properties were achieved. The utilization of high-quality flux VTM pellets could enhance production efficiency and reduce energy consumption. Further research was suggested from viewpoints of elucidating the microscopic mechanisms involved in the consolidation and reduction of these pellets，as well as developing methods to prepare high-quality VTM pellets，can offer theoretical and technical support for the efficient utilization of VTM resources，could lay the material foundation for the clean charge and efficient utilization of VTM. Additionally，this research held significant guiding significance for the production and application of other types of complex iron flux pellets and low carbon green environment.